diff options
Diffstat (limited to 'src/Xmobar')
-rw-r--r-- | src/Xmobar/App/EventLoop.hs | 43 | ||||
-rw-r--r-- | src/Xmobar/App/Main.hs | 21 | ||||
-rw-r--r-- | src/Xmobar/App/Timer.hs | 130 | ||||
-rw-r--r-- | src/Xmobar/Run/Exec.hs | 5 |
4 files changed, 177 insertions, 22 deletions
diff --git a/src/Xmobar/App/EventLoop.hs b/src/Xmobar/App/EventLoop.hs index 3fab3e5..f6ab932 100644 --- a/src/Xmobar/App/EventLoop.hs +++ b/src/Xmobar/App/EventLoop.hs @@ -17,7 +17,12 @@ ------------------------------------------------------------------------------ -module Xmobar.App.EventLoop (startLoop, startCommand) where +module Xmobar.App.EventLoop + ( startLoop + , startCommand + , newRefreshLock + , refreshLock + ) where import Prelude hiding (lookup) import Graphics.X11.Xlib hiding (textExtents, textWidth) @@ -31,7 +36,7 @@ import Control.Monad.Reader import Control.Concurrent import Control.Concurrent.Async (Async, async) import Control.Concurrent.STM -import Control.Exception (handle, SomeException(..)) +import Control.Exception (bracket_, handle, SomeException(..)) import Data.Bits import Data.Map hiding (foldr, map, filter) import Data.Maybe (fromJust, isJust) @@ -63,15 +68,34 @@ import Xmobar.System.DBus runX :: XConf -> X () -> IO () runX xc f = runReaderT f xc +newRefreshLock :: IO (TMVar ()) +newRefreshLock = atomically $ newTMVar () + +refreshLock :: TMVar () -> IO a -> IO a +refreshLock var = bracket_ lock unlock + where + lock = atomically $ takeTMVar var + unlock = atomically $ putTMVar var () + +refreshLockT :: TMVar () -> STM a -> STM a +refreshLockT var action = do + takeTMVar var + r <- action + putTMVar var () + return r + -- | Starts the main event loop and threads -startLoop :: XConf -> TMVar SignalType -> [[([Async ()], TVar String)]] - -> IO () -startLoop xcfg@(XConf _ _ w _ _ _ _) sig vs = do +startLoop :: XConf + -> TMVar SignalType + -> TMVar () + -> [[([Async ()], TVar String)]] + -> IO () +startLoop xcfg@(XConf _ _ w _ _ _ _) sig pauser vs = do #ifdef XFT xftInitFtLibrary #endif tv <- atomically $ newTVar [] - _ <- forkIO (handle (handler "checker") (checker tv [] vs sig)) + _ <- forkIO (handle (handler "checker") (checker tv [] vs sig pauser)) #ifdef THREADED_RUNTIME _ <- forkOS (handle (handler "eventer") (eventer sig)) #else @@ -111,15 +135,16 @@ checker :: TVar [String] -> [String] -> [[([Async ()], TVar String)]] -> TMVar SignalType + -> TMVar () -> IO () -checker tvar ov vs signal = do - nval <- atomically $ do +checker tvar ov vs signal pauser = do + nval <- atomically $ refreshLockT pauser $ do nv <- mapM concatV vs guard (nv /= ov) writeTVar tvar nv return nv atomically $ putTMVar signal Wakeup - checker tvar nval vs signal + checker tvar nval vs signal pauser where concatV = fmap concat . mapM (readTVar . snd) diff --git a/src/Xmobar/App/Main.hs b/src/Xmobar/App/Main.hs index 29504f4..e0b0329 100644 --- a/src/Xmobar/App/Main.hs +++ b/src/Xmobar/App/Main.hs @@ -40,9 +40,10 @@ import Xmobar.X11.Types import Xmobar.X11.Text import Xmobar.X11.Window import Xmobar.App.Opts (recompileFlag, verboseFlag, getOpts, doOpts) -import Xmobar.App.EventLoop (startLoop, startCommand) +import Xmobar.App.EventLoop (startLoop, startCommand, newRefreshLock, refreshLock) import Xmobar.App.Compile (recompile, trace) import Xmobar.App.Config +import Xmobar.App.Timer (withTimer) xmobar :: Config -> IO () xmobar conf = withDeferSignals $ do @@ -53,14 +54,16 @@ xmobar conf = withDeferSignals $ do cls <- mapM (parseTemplate (commands conf) (sepChar conf)) (splitTemplate (alignSep conf) (template conf)) sig <- setupSignalHandler - bracket (mapM (mapM $ startCommand sig) cls) - cleanupThreads - $ \vars -> do - (r,w) <- createWin d fs conf - let ic = Map.empty - to = textOffset conf - ts = textOffsets conf ++ replicate (length fl) (-1) - startLoop (XConf d r w (fs:fl) (to:ts) ic conf) sig vars + refLock <- newRefreshLock + withTimer (refreshLock refLock) $ + bracket (mapM (mapM $ startCommand sig) cls) + cleanupThreads + $ \vars -> do + (r,w) <- createWin d fs conf + let ic = Map.empty + to = textOffset conf + ts = textOffsets conf ++ replicate (length fl) (-1) + startLoop (XConf d r w (fs:fl) (to:ts) ic conf) sig refLock vars configFromArgs :: Config -> IO Config configFromArgs cfg = getArgs >>= getOpts >>= doOpts cfg . fst diff --git a/src/Xmobar/App/Timer.hs b/src/Xmobar/App/Timer.hs new file mode 100644 index 0000000..d67695d --- /dev/null +++ b/src/Xmobar/App/Timer.hs @@ -0,0 +1,130 @@ +------------------------------------------------------------------------------ +-- | +-- Module: Xmobar.App.Timer +-- Copyright: (c) 2019 Tomáš Janoušek +-- License: BSD3-style (see LICENSE) +-- +-- Maintainer: Tomáš Janoušek <tomi@nomi.cz> +-- Stability: unstable +-- +-- Timer coalescing for recurring actions. +-- +------------------------------------------------------------------------------ + +module Xmobar.App.Timer (doEveryTenthSeconds, withTimer) where + +import Control.Concurrent.Async (withAsync) +import Control.Concurrent.STM +import Control.Exception (bracket, bracket_) +import Control.Monad (forever, forM, forM_, guard) +import Data.IORef +import Data.Int (Int64) +import Data.Map (Map) +import qualified Data.Map as M +import Data.Time.Clock.POSIX (getPOSIXTime) +import Data.Unique +import System.IO.Unsafe (unsafePerformIO) + +newtype Timer = Timer (TVar Periods) + +type Periods = Map Unique Period + +data Period = Period { rate :: Int64, next :: Int64, tick :: TMVar (TMVar ()) } + +{-# NOINLINE timer #-} +timer :: IORef (Maybe Timer) +timer = unsafePerformIO (newIORef Nothing) + +now :: IO Int64 +now = do + posix <- getPOSIXTime + return $ floor (10 * posix) + +newPeriod :: Int64 -> IO (Unique, Period) +newPeriod r = do + u <- newUnique + t <- now + v <- atomically newEmptyTMVar + let t' = t - t `mod` r + return (u, Period { rate = r, next = t', tick = v }) + +-- | Perform a given action every N tenths of a second. +-- +-- The timer is aligned with other timers to minimize the number of wakeups +-- and unnecessary redraws. +doEveryTenthSeconds :: Int -> IO () -> IO () +doEveryTenthSeconds r action = do + Just t <- readIORef timer + doEveryTenthSeconds' t r action + +doEveryTenthSeconds' :: Timer -> Int -> IO () -> IO () +doEveryTenthSeconds' (Timer periodsVar) r action = do + (u, p) <- newPeriod (fromIntegral r) + bracket_ (push u p) (pop u) $ forever $ + bracket (atomically $ takeTMVar $ tick p) + (\doneVar -> atomically $ putTMVar doneVar ()) + (const action) + where + push u p = atomically $ modifyTVar periodsVar (M.insert u p) + pop u = atomically $ modifyTVar periodsVar (M.delete u) + +-- | Start the timer coordination thread. +withTimer :: (IO () -> IO ()) -> IO a -> IO a +withTimer pauseRefresh action = do + periodsVar <- atomically $ newTVar M.empty + withAsync (timerLoop pauseRefresh periodsVar) $ \_ -> + bracket_ + (writeIORef timer (Just (Timer periodsVar))) + (writeIORef timer Nothing) -- TODO: kill all periods? + action + +timerLoop :: (IO () -> IO ()) -> TVar Periods -> IO () +timerLoop pauseRefresh periodsVar = forever $ do + t <- now + toFire <- atomically $ do + periods <- readTVar periodsVar + writeTVar periodsVar (advanceTimers t periods) + return (timersToFire t periods) + pauseRefresh $ do + -- Fire timers ... + doneVars <- atomically $ forM toFire $ \p -> do + doneVar <- newEmptyTMVar + putTMVar (tick p) doneVar + return doneVar + -- ... and wait for them to avoid unnecessary redraws. + atomically $ forM_ doneVars takeTMVar + delayUntilNextFire periodsVar + +advanceTimers :: Int64 -> Periods -> Periods +advanceTimers t = M.map advance + where + advance p | next p <= t = p { next = t - t `mod` rate p + rate p } + | otherwise = p + +timersToFire :: Int64 -> Periods -> [Period] +timersToFire t periods = [ p | p <- M.elems periods, next p <= t ] + +nextFireTime :: Periods -> Maybe Int64 +nextFireTime periods + | M.null periods = Nothing + | otherwise = Just $ minimum [ next p | p <- M.elems periods ] + +delayUntilNextFire :: TVar Periods -> IO () +delayUntilNextFire periodsVar = do + tMaybeNext <- fmap nextFireTime $ readTVarIO periodsVar + tNow <- now + delayVar <- case tMaybeNext of + Just tNext -> do + -- Work around the Int max bound: threadDelay takes an Int, we can + -- only sleep for so long, which is okay, we'll just check timers + -- sooner and sleep again. + let maxDelay = (maxBound :: Int) `div` 100000 + delay = (tNext - tNow) `min` fromIntegral maxDelay + delayUsec = fromIntegral delay * 100000 + registerDelay delayUsec + Nothing -> atomically $ newTVar False + atomically $ do + delayOver <- readTVar delayVar + tMaybeNext' <- fmap nextFireTime $ readTVar periodsVar + -- Return also if a new period is added (it may fire sooner). + guard $ delayOver || tMaybeNext /= tMaybeNext' diff --git a/src/Xmobar/Run/Exec.hs b/src/Xmobar/Run/Exec.hs index db7e7b4..ad68232 100644 --- a/src/Xmobar/Run/Exec.hs +++ b/src/Xmobar/Run/Exec.hs @@ -23,6 +23,7 @@ import Prelude import Data.Char import Control.Concurrent +import Xmobar.App.Timer (doEveryTenthSeconds) import Xmobar.System.Signal -- | Work around to the Int max bound: since threadDelay takes an Int, it @@ -34,10 +35,6 @@ tenthSeconds s | s >= x = do threadDelay (x * 100000) | otherwise = threadDelay (s * 100000) where x = (maxBound :: Int) `div` 100000 -doEveryTenthSeconds :: Int -> IO () -> IO () -doEveryTenthSeconds r action = go - where go = action >> tenthSeconds r >> go - class Show e => Exec e where alias :: e -> String alias e = takeWhile (not . isSpace) $ show e |